Read Cart

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: the auth requirement (local account login) and a privacy guarantee that no address, phone, cookies or payment data are returned.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, zero waste, with the resource and the returned fields front-loaded and the auth/privacy caveats after. Nothing could be cut without losing information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return-value documentation is not required in the description. Combined with the annotations and the auth/privacy notes, this is nearly complete for a zero-parameter read tool; only the sibling disambiguation from read_account_cart is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, and the schema is fully described at 100% coverage, so the baseline of 4 applies. There is no parameter semantics the description needs to compensate for.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (read the connected account's cart) and enumerates what it returns (cart items, offers, unit prices, quantities). However, it does not distinguish itself from the sibling read_account_cart, which by name sounds like the same operation, leaving a real ambiguity for the agent.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It states a prerequisite ("Requires local account login"), which is useful context. But it gives no when-to-use/when-not guidance and never clarifies how this differs from read_account_cart or the other cart readers, so selection among siblings is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.